Question

Rushawn lined up the interior angles of the triangle along line p below.

Triangle A B C. Angles A, B, and C are shown on line p.

When the measure of angle C decreases, what happens to the measures of angles A and B on line p?
Both sections increase.
Both sections decrease.
One section increases, and the other section decreases.
What will happen to the individual sections cannot be determined, but the size of the two sections together increases.

Answer 1

Because A + B + C = 180°, if C decreases by some amount then A + B must increase by that same amount. So the combined size of the two sections (A and B) increases. However, you cannot tell how that increase is split between A and B from the information given — both could increase, or one could increase while the other decreases.

Therefore: "What will happen to the individual sections cannot be determined, but the size of the two sections together increases."